Chemical stability of MgO/CaO/Cr2O3-Al2O3-B2O3-phosphate glasses in solid oxide fuel cell environment

The thermal properties, glass forming tendency and glass stability in solid oxide fuel cell (SOFC) relevant atmospheres have been determined for four different refractory MgO/CaO/Cr2O3-Al2O3-B2O3 phosphate based glasses. Also , the bonding ability and interaction as a function of temperature between the glasses and La0.8Ca0.22CrO3 interconnect material have been studied. Th e microstructural characterization and elemental analysis of reaction coupl es reveal that the bonding ability and interface interaction is closely rel ated to the CaO content and the relative glass forming tendency. The reacti ons at 1000 degrees C between the glass and the solid interconnect material for the high CaO or MgO containing compositions occur by a liquid phase or a vapour phase mechanism, respectively. The reaction at 1200 degrees C in both cases occurs by a liquid phase mechanism. (C) 1998 Chapman & Hall.